Articoli di riviste: "“Stratigraphic” method"

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Mai, Hoàng Đảm, e Thị Thắm Nguyễn. "Biostratigraphic characteristics and correction of the boundary between Miocene and Oligocene sediments in the northern Malay - Tho Chu basin". Petrovietnam Journal 5 (4 luglio 2022): 19–27. http://dx.doi.org/10.47800/pvj.2022.05-03.

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Stratigraphic study in oil and gas wells is dependent on the research method and the characteristics of the collected samples, such as sample types and spaces between samples, that is why the stratigraphic boundary of the wells may fluctuate in a certain sedimentary range. Therefore, when re-evaluating the hydrocarbon potential or expanding the petroleum exploration targets of an area, we need to study additional evidence and geological events to correct the stratigraphic boundary of the well and correlate regional stratigraphy. These studies often use biostratigraphic and seismic stratigraphic methods. This paper provides evidence on biostratigraphy to correct the stratigraphic boundary between Miocene and Oligocene sediments in the northern Malay - Tho Chu basin and compares them with the general stratigraphy of the Malay basin. The research results determined that the top of the Oligocene sediment after correcting is higher than what was specified in the previous studies based on marker fossil findings in a palynomorph abundance cycle; and there are similar biostratigraphic characteristics between the studied area and the Malay basin.

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Chernykh, V. V. "Zonal biochronological method for solving long-living problems of general stratigraphy". LITHOSPHERE (Russia) 23, n. 6 (29 dicembre 2023): 935–49. http://dx.doi.org/10.24930/1681-9004-2023-23-6-935-949.

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Research subject. Problematic issues of general stratigraphy are considered, including the Karpinsky principle, the unification of autonomous zonal biochronological scales (BCS), the basics of stratigraphic classification, the relation of zonal biostratigraphic and chronostratigraphic units. Materials and methods. The existing standard solutions to the above issues are analyzed. An attempt is made to reveal the logical sources of contradictions and to pave ways for a consistent synthesis. Results. The necessity for a successful solution of these issues to abandon the identification of the biochronological scale and the geological section is shown. From the recognition of the zone as the smallest subdivision of the biochronological scale, the linearity of the zonal subdivisions of the scale follows, which makes it a correct tool for performing basic stratigraphic operations – section subdivision and correlation of the boundaries of stratigraphic units. Strict differentiation of the scale from a section studied using this scale makes it possible to fulfill all the requirements of the Karpinsky principle regarding dividing horizons with mixed fauna. The same condition underlies the creation of a stratigraphic classification, which must be preceded by a clear separation of the material (“mapped”) stratigraphic units of the Earth’s crust and units of chronological scales, which are used for their correlation. Placing them in a single “dualistic” stratigraphic classification cannot give a satisfactory result. The creation of autonomous zonal scales should be preceded by the definition of the biozones of the species used to build these scales, according to the normative (standard) zonal scale for a given stratigraphic interval. Taking into account the minimum dimension of the zonal subdivisions of the standard scale, the zones of autonomous scales distinguished by this method correspond to a whole number of normative zones, and, therefore, the boundaries of the stratozones established on the autonomous scales, in this case, will certainly coincide with any boundaries of the stratozones, distinguished on the normative scale. This procedure makes it possible to perform the unification of autonomous zonal BCSs based on different groups of fossils. Zonal BCS performs correlation functions, zonal units are a tool for chronological identification of remote geological objects, including the boundaries of chronostratigraphic units, although not being included in their hierarchy. Conclusions. A biochronological scale is a model of the biochronological calculation of geological time and cannot be identical to what it models. Differentiation of the scale from a section studied using this scale is an indispensable condition that precedes and ensures the successful solution of long-living problems of general stratigraphy.

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Prather, Bradford E., Oriol Falivene e Peter M. Burgess. "Stratigraphic analysis of XES02: Implications for the sequence stratigraphic paradigm". Journal of Sedimentary Research 92, n. 10 (19 ottobre 2022): 934–54. http://dx.doi.org/10.2110/jsr.2022.008.

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ABSTRACT Sequence stratigraphy has the potential to provide a consistent method for integrating data, correlating strata, defining stratigraphic evolution, and generating quantifiable predictions. However, the consistent application requires a precise definition of concepts, stratigraphic units, bounding surfaces, and workflow. Currently no single generally accepted approach to sequence stratigraphic analysis exists, nor are there any robust tests of models and methods. Applying conventional sequence stratigraphic analysis to strata from an analog laboratory experiment (eXperimental EarthScape02, XES02) with known boundary conditions and chronology provides some initial robust testing of the models and methods. Despite stratigraphic architectures apparently consistent with those expected within the sequence stratigraphic paradigm, blind-test applications yield: 1) deducted erroneous base-level curves, 2) systems-tract classification mismatches, 3) disconnected systems-tracts type and actual base level, 4) time-transgressive basin-floor fans, and 5) missing systems tracts. Stratigraphic forward models using base-level curves derived from Wheeler diagrams cannot match the timing, redeposited-sediment volume, and depositional environments observed in the XES02 experiment. These mismatches result from common Wheeler diagram construction practice, producing poorly resolved base-level minima timing and base-level fall durations, hence inaccurate fall rates. Consequently, reconstructions of controlling factors based on stratal architectures remain uncertain, making predictions similarly uncertain. A reasonable path forward is to properly acknowledge these uncertainties while performing stratigraphic analysis and to address them through multiple scenario analysis and modeling.

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Meng, Peng, Li Liu, Xiaoming Sun, Yuqiao Gao e Xiyu Qu. "An application of micropaleontology-sequence stratigraphy method in stratigraphic division". Frontiers of Earth Science in China 1, n. 2 (maggio 2007): 157–64. http://dx.doi.org/10.1007/s11707-007-0020-7.

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Xiao, Zheng. "Application of Seismic Stratigraphic Slice Continuous Browsing Technology to Delicately Characterize River Sedimentary Microfacies". International Journal of Energy 2, n. 3 (23 maggio 2023): 42–45. http://dx.doi.org/10.54097/ije.v2i3.8808.

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On the basis of understanding the regional tectonics characteristics and stratigraphic sedimentary characteristics of the study area, the sequence stratigraphic framework within the region is gradually studied by applying the principle of high-resolution sequence stratigraphy, and G4 oil formation is divided into three sets of sand formations, namely, G4 upper, G4 middle, and G4 lower sand formations, and divided into small layers in detail. Through comprehensive analysis of lithofacies, logging facies, and seismic facies, the sedimentary facies of the G4 oil formation are comprehensively analyzed. The main sedimentary facies type of the G4 oil formation is the delta front facies belt, and the most important sedimentary microfacies in the delta front facies belt are underwater distributary channel sedimentary microfacies. Using seismic sedimentology methods, make stratigraphic slices of each sub layer of the G4 oil formation, and use the rapid browsing method of stratigraphic slices to trace river sand in detail.

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Reilly, Mark, Suzanne Hurter, Zsolt Hamerli, Claudio L. de Andrade Vieira Filho, Andrew LaCroix e Sebastian Gonzalez. "An integrated approach to the Surat Basin stratigraphy". APPEA Journal 59, n. 2 (2019): 940. http://dx.doi.org/10.1071/aj18073.

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The stratigraphy of the Surat Basin, Queensland, has historically been sub-divided by formation and unit nomenclature with a few attempts by other authors to apply sequence stratigraphy to existing formation boundaries. At a local- to field-scale, lithostratigraphy may be able to represent stratigraphy well, but at regional-scale, lithostratigraphic units are likely to be diachronous. To date, this lithology-driven framework does not accurately reflect time relationships in the sub-surface. An entirely new integrated methodological approach, involving well tied seismic data and sequence stratigraphic well-to-well correlations compared with published zircon age dates, has been applied to hundreds of deep wells and shallower coal seam gas wells. This method sub-divides the Surat Basin stratigraphy into defendable 2nd order to 3rd order sequence stratigraphic cycles and has required the use of an alpha-numeric sequence stratigraphic nomenclature to adequately and systematically label potential time equivalent surfaces basin-wide. Correlation of wells is the first step in building models of aquifers and coal seam gas fields for numerical simulation of fluid flow, which is necessary for responsible resource management. Lithostratigraphic correlations will overestimate the extent and hydraulic connectedness of the strata of interest. The result may be fluid flow models that do not represent a realistic pressure footprint of the flow. The present sequence stratigraphic method more accurately reflects the disconnectedness of sub-surface coals and sandstones (aquifers) on a field-to-field scale, adjacent field-scale, and basin-wide scale. It forms the basis for improved and more representative modelling of the sub-surface.

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Ji, Da Wei, Ji Li e Guang Dong Lu. "Application of Wavelet Transform in High-Resolution Sequence Stratigraphic Division". Advanced Materials Research 772 (settembre 2013): 823–27. http://dx.doi.org/10.4028/www.scientific.net/amr.772.823.

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In this paper, the method and effect of logging curves wavelet transform in high-resolution sequence division are discussed, taking the middle oil sequence stratigraphic of DU-432 oil well in north-Songliao basin as an example. Using Wavelet Transform to GR logging curves, the relationship between logging curve signals and depth is transformed to the relationship between the depth and the scale domain, so that the wavelet curves in different scale are obtained. Then the relationship between the periodic oscillation characteristics of the wavelet curves under the best optimal scale factor and the sequence. Comparing the Sequence Stratigraphic Division by wavelet transform with the manual division, Results show that the Division by Sequence Stratigraphic wavelet transform is more objective and more effective and the Division provides a new way to high-resolution sequence stratigraphy.

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Lai, Fu-qiang, Zhao-Hui Huang, Zhang-xiong Zhu, Shao-hua Xu, Wei-xu Xia e Han Luo. "Monte Carlo CLEAN Spectral Analysis Method for Detecting the Stratigraphic Cycles Based on High-resolution Electrical Image Log Data". Journal of Environmental and Engineering Geophysics 22, n. 4 (dicembre 2017): 325–37. http://dx.doi.org/10.2113/jeeg22.4.325.

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This paper performs a Monte Carlo CLEAN (MC-CLEAN) spectral analysis with high-resolution electrical image log data and interpret the high-resolution formation sequence by investigating the cycles in the sediments. Firstly, in order to perform a spectral analysis with high-resolution electrical image log data, the background conductivity log curve was extracted from the borehole image. Secondly, the MC-CLEAN spectrum analysis method was used to isolate all the peaks of the logging signal. Then the 95% significance level of the CLEAN spectrum was calculated to identify the true period of the formation by Monte Carlo simulation. Finally, the MC-CLEAN spectral analysis method was applied in the two shale intervals from Lower Pannonian interval of Vienna basin to identify the stratigraphic cycles. The analysis results showed that the identified cycles in the sedimentary record good matched the Milankovitch cycles. This paper provided a new approach of identifying stratigraphic cycles and interpreting high-resolution sequence stratigraphy.

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Edwards, Jonathan, Florent Lallier, Guillaume Caumon e Cédric Carpentier. "Uncertainty management in stratigraphic well correlation and stratigraphic architectures: A training-based method". Computers & Geosciences 111 (febbraio 2018): 1–17. http://dx.doi.org/10.1016/j.cageo.2017.10.008.

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Maravelis, Angelos G., Jake Breckenridge, Kevin Ruming, Erin Holmes, Yuri Amelin e William J. Collins. "Re-assessing the Upper Permian Stratigraphic Succession of the Northern Sydney Basin, Australia, by CA-IDTIMS". Geosciences 10, n. 11 (22 novembre 2020): 474. http://dx.doi.org/10.3390/geosciences10110474.

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High precision Chemical abrasion-isotope dilution thermal ionisation mass spectrometry (CA-IDTIMS) U-Pb zircon results from tuff marker beds that are interstratified within the Upper Permian deposits of the northern Sydney Basin add constraints on the timing of sediment deposition, and afford a better understanding of the regional stratigraphy. The results indicate a magmatic influence during the deposition of the sediments, with episodic events spanning at least from 255.65 ± 0.08 to 255.08 ± 0.09 Ma. The zircon data suggest that the studied sedimentary rocks and tuffs have accumulated simultaneously over a short time interval, which contrasts with current stratigraphic models that suggest a much greater period of deposition and stratigraphic thickness. Therefore, an updated stratigraphic correlation of the basin is suggested, which combines the presently defined Lambton, Adamstown, and Boolaroo sub-groups into a single Lambton sub-group. This updated correlation framework is stratigraphically and geochronologically constrained and provides a more precise exploration model for the northern Sydney Basin. This case study highlights the valuable contribution of the CA-IDTIMS method in intrabasinal correlations of sedimentary successions, when integrated with a robust sedimentological framework, to minimize the stratigraphic uncertainties.

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Busetti, Seth. "A method for modeling multiscale geomechanical effects in the stimulated rock volume". Interpretation 9, n. 1 (7 gennaio 2021): T45—T61. http://dx.doi.org/10.1190/int-2020-0090.1.

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I have developed a workflow to efficiently simulate geomechanical effects in the stimulated rock volume (SRV) by including regional geologic structures such as faults and folds as well as high-resolution-oriented mechanical stratigraphy. The motivation is that the local model used for hydraulic fracture analysis should include macroscale 3D geomechanical effects derived from regional tectonic and seismic data. A practical computational strategy is developed to link multiple 3D geomechanical models derived at different scales and their associated stress effects. I apply the workflow to a synthetic reservoir problem composed of a tectonic-scale structural framework model with three embedded mechanical stratigraphic models representing three stimulated vertical wells. I first combine regional stresses solved with 3D finite-element analysis with perturbation stresses from elastic dislocation modeling using elastic superposition concepts. I then apply the macroscale stress effects as unique boundary conditions to an embedded finite-element submodel, a mesoscale stratigraphic model representing the SRV allowing for resolution of variable stress amplification, and stress rotation in geologic sublayers. Finally, I conduct hydraulic-fracture simulations within the SRV models. The simulated hydraulic fractures are controled by the structural position and mechanical stratigraphy. Closest to the back limb of the main structural anticline, hydraulic fractures tend to be height-restricted, and in some realizations, fractures propagate horizontally. Adjacent to the fold and a fault, where differential stresses are elevated, fracture growth is the most unconstrained in height and length. Results suggest that this multiscale approach can be applied to better predict and understand behaviors related to unconventional reservoir stimulation. The workflow could easily be modified for other operational problems and geologic settings.

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Ding, Xuesong, Tristan Salles, Nicolas Flament e Patrice Rey. "Quantitative stratigraphic analysis in a source-to-sink numerical framework". Geoscientific Model Development 12, n. 6 (28 giugno 2019): 2571–85. http://dx.doi.org/10.5194/gmd-12-2571-2019.

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Abstract. The sedimentary architecture at continental margins reflects the interplay between the rate of change of accommodation creation (δA) and the rate of change of sediment supply (δS). Stratigraphic interpretation increasingly focuses on understanding the link between deposition patterns and changes in δA∕δS, with an attempt to reconstruct the contributing factors. Here, we use the landscape modelling code pyBadlands to (1) investigate the development of stratigraphic sequences in a source-to-sink context; (2) assess the respective performance of two well-established stratigraphic interpretation techniques: the trajectory analysis method and the accommodation succession method; and (3) propose quantitative stratigraphic interpretations based on those two techniques. In contrast to most stratigraphic forward models (SFMs), pyBadlands provides self-consistent sediment supply to basin margins as it simulates erosion, sediment transport and deposition in a source-to-sink context. We present a generic case of landscape evolution that takes into account periodic sea level variations and passive margin thermal subsidence over 30 million years, under uniform rainfall. A set of post-processing tools are provided to analyse the predicted stratigraphic architecture. We first reconstruct the temporal evolution of the depositional cycles and identify key stratigraphic surfaces based on observations of stratal geometries and facies relationships, which we use for comparison to stratigraphic interpretations. We then apply both the trajectory analysis and the accommodation succession methods to manually map key stratigraphic surfaces and define sequence units on the final model output. Finally, we calculate shoreline and shelf-edge trajectories, the temporal evolution of changes in relative sea level (proxy for δA) and sedimentation rate (proxy for δS) at the shoreline, and automatically produce stratigraphic interpretations. Our results suggest that the analysis of the presented model is more robust with the accommodation succession method than with the trajectory analysis method. Stratigraphic analysis based on manually extracted shoreline and shelf-edge trajectory requires calibrations of time-dependent processes such as thermal subsidence or additional constraints from stratal terminations to obtain reliable interpretations. The 3-D stratigraphic analysis of the presented model reveals small lateral variations of sequence formations. Our work provides an efficient and flexible quantitative sequence stratigraphic framework to evaluate the main drivers (climate, sea level and tectonics) controlling sedimentary architectures and investigate their respective roles in sedimentary basin development.

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Wu, Xinming. "Directional structure-tensor-based coherence to detect seismic faults and channels". GEOPHYSICS 82, n. 2 (1 marzo 2017): A13—A17. http://dx.doi.org/10.1190/geo2016-0473.1.

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Seismic coherence is widely used in seismic interpretation and reservoir characterization to highlight (with low values) faults and stratigraphic features from a seismic image. A coherence image can be computed from the eigenvalues of conventional structure tenors, which are outer products of gradients of a seismic image. I have developed a simple but effective method to improve such a coherence image by using directional structure tensors, which are different from the conventional structure tensors in only two aspects. First, instead of using image gradients with vertical and horizontal derivatives, I use directional derivatives, computed in directions perpendicular and parallel to seismic structures (reflectors), to construct directional structure tensors. With these directional derivatives, lateral seismic discontinuities, especially those subtle stratigraphic features aligned within dipping structures, can be better captured in the structure tensors. Second, instead of applying Gaussian smoothing to each element of the constructed structure tensors, I apply approximately fault- and stratigraphy-oriented smoothing to enhance the lateral discontinuities corresponding to faults and stratigraphic features in the structure tensors. Real 3D examples show that the new coherence images computed from such structure tensors display much cleaner and more continuous faults and stratigraphic features compared with those computed from conventional structure tensors and covariance matrices.

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Lessenger, Margaret A., e Timothy A. Cross. "An Inverse Stratigraphic Simulation Model – Is Stratigraphic Inversion Possible?" Energy Exploration & Exploitation 14, n. 6 (dicembre 1996): 627–37. http://dx.doi.org/10.1177/014459879601400606.

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Inversion is a systematic method of determining values of process parameters of a forward model that allow a match between observed and modeled data. Historically, geologists have considered the stratigraphic record to be nonunique. That is, geologists have assumed that it is impossible to determine values for and separate stratigraphic process variables such as eustasy, tectonics and sediment supply that operated to form the stratigraphic record. If stratigraphic data are nonunique, then inversion of stratigraphic data is impossible. In an influential paper. Burton et al. (1987) argued that inversion of stratigraphic data using a stratigraphic forward model is not possible. The purpose of this study was to determine if inversion of stratigraphic data using a stratigraphic forward model is theoretically possible. In this study, we designed a stratigraphic inverse simulation model using a forward stratigraphic model capable of simulating realistic temporal and spatial distributions of fades tracts and stratigraphic surfaces. For numerical optimization, we used a gradient descent method that minimizes errors in the least squares sense. We tested this inverse model on synthetic stratigraphic data which act as a proxy for real-world stratigraphic data, to test multiple aspects of the inverse model. In these experiments, we inverted synthetic stratigraphic data for eustasy, sediment supply, tectonic subsidence, lithosphere flexural rigidity, and initial basin topography. Results from these inversion experiments establish that inversion of stratigraphic data is theoretically possible. We determined limits of convergence, degrees of parameter separatability, nonuniqueness of data, and types of data necessary for inversion. Results suggest that using distributions of facies tracts and stratigraphic surfaces within a genetic sequence stratigraphic framework is necessary for inversion. Results from inverse model experiments also suggest that nonuniqueness of these data types with respect to stratigraphic process parameters such as eustasy, tectonics, sediment supply and depositional topography is bounded. Moreover, the bounds of nonuniqueness are quite small. The next phase of our research is to first test an inverse algorithm that is more appropriate for stratigraphic inversion, and then to test an inverse stratigraphic model using a real stratigraphic data set.

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Abdullah, Agus, e Waskito Pranowo. "Layer-steered filter for enhancing seismic reflection interpretability". Journal of Petroleum Exploration and Production Technology 10, n. 8 (3 settembre 2020): 3235–39. http://dx.doi.org/10.1007/s13202-020-00994-2.

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Abstract Seismic artifacts due to random and linear noises, low fold coverage, statics, and spatial aliasing are frequently affecting uncertainties in seismic interpretation. Several conventional methods, such as median filter, have been implemented to reduce random noises. However, this method can not be utilized for the area in which rich with stratigraphic features such as clinoforms and in the area with strong dips. We implemented layer-steered filter in order to attenuate random noises in this kind of situation. Layer-steered filter has ability to attenuate random noises but still respects to local dip events; therefore, the method provides better preservation of events and stratigraphics compared to other conventional methods such as median filter and dip-steered filter.

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Wang, Steve C., Philip J. Everson, Heather Jianan Zhou, Dasol Park e David J. Chudzicki. "Adaptive credible intervals on stratigraphic ranges when recovery potential is unknown". Paleobiology 42, n. 2 (19 febbraio 2016): 240–56. http://dx.doi.org/10.1017/pab.2015.37.

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AbstractNumerous methods exist for estimating the true stratigraphic range of a fossil taxon based on the stratigraphic positions of its fossil occurrences. Many of these methods require the assumption of uniform fossil recovery potential—that fossils are equally likely to be found at any point within the taxon's true range. This assumption is unrealistic, because factors such as stratigraphic architecture, sampling effort, and the taxon's abundance and geographic range affect recovery potential. Other methods do not make this assumption, but they instead require a priori quantitative knowledge of recovery potential that may be difficult to obtain. We present a new Bayesian method, the Adaptive Beta method, for estimating the true stratigraphic range of a taxon that works for both uniform and non-uniform recovery potential. In contrast to existing methods, we explicitly estimate recovery potential from the positions of the occurrences themselves, so that a priori knowledge of recovery potential is not required. Using simulated datasets, we compare the performance of our method with existing methods. We show that the Adaptive Beta method performs well in that it achieves or nearly achieves nominal coverage probabilities and provides reasonable point estimates of the true extinction in a variety of situations. We demonstrate the method using a dataset of the Cambrian molluscAnabarella.

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Lévesque, Yan, Julien Walter e Romain Chesnaux. "Transient Electromagnetic (TEM) Surveys as a First Approach for Characterizing a Regional Aquifer: The Case of the Saint-Narcisse Moraine, Quebec, Canada". Geosciences 11, n. 10 (6 ottobre 2021): 415. http://dx.doi.org/10.3390/geosciences11100415.

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Geological contexts that lack minimal stratigraphic and piezometric information can be challenging to produce an initial hydrogeological map in remote territories. This study proposes an approach to characterize a regional aquifer using transient electromagnetic (TEM) surveys. Given the presence of randomly dispersed boreholes, the Saint-Narcisse moraine in the Mauricie region of Quebec (Canada) is an appropriate site for collecting the required geophysical data, correlating the stratigraphic and piezometric information, and characterizing regional granular aquifers in terms of stratigraphy, geometry, thickness, and extent. In order to use all TEM results (i.e., 47 stations) acquired in the moraine area, we also correlated 13 TEM stations, 7 boreholes, and 6 stratigraphic cross-sections to derive an empirical and local petrophysical relationship and to establish a calibration chart of the sediments. Our TEM data, combined with piezometric mapping and the sedimentary records from boreholes and stratigraphic cross-sections, revealed the compartmentalization of a multi-kilometer morainic system and indicated the presence of two large unconfined granular aquifers overlying the bedrock. These aquifers extend more than 12 km east to west across the study area and are between 25 and >94 m thick. The TEM method provides critical information on groundwater at a regional scale by acquiring information from multiple stations within a short time span to a degree not possible with other existing methodologies.

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Carpenter, Chris. "Stratigraphic Forward Modeling Assists Carbonate-Reservoir Characterization". Journal of Petroleum Technology 74, n. 09 (1 settembre 2022): 60–63. http://dx.doi.org/10.2118/0922-0060-jpt.

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_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 202775, “Application of Stratigraphic Forward Modeling to Carbonate-Reservoir Characterization: A New Paradigm From the Albion Research and Development Project,” by Jean Borgomano, Aix-Marseille University, and Gérard Massonnat and Cyprien Lanteaume, TotalEnergies, et al. The paper has not been peer reviewed. _ Improving carbonate-reservoir prediction, field development, and production forecasts, especially in zones lacking data, requires novel reservoir-modeling approaches, including process-based methods. Classical geostatistic modeling methods alone cannot match this challenge, particularly if subtle stratigraphic architectures or sedimentary and diagenetic geometries not directly identified as properties with well data control the reservoir heterogeneity. Stratigraphic forward-modeling approaches can provide pertinent information to carbonate-reservoir characterization. The complete paper describes a modeling package tested and calibrated with high-resolution stratigraphic outcrop models. It allows valid prediction of carbonate facies associations mimicking the spatial distribution mapped along the Urgonian platform transects. Background Classical carbonate-reservoir characterization protocols rely mainly on 3D geostatistical models based on well data, allowing the realization of 3D numerical grids of reservoir properties. These geostatistic property models are supported by deterministic geological interpretations such as stratigraphic well correlations that are commonly based on sequenced stratigraphic concepts and carbonate sedimentological interpretations. The stratigraphic framework obtained from these deterministic interpretations has a critical effect on further static and dynamic reservoir models because it constrains the spatial stationarity of the geostatistic property simulations or imposes discrete flow units or barriers. These deterministic carbonate sequence stratigraphic and associated sedimentological interpretations, however, introduce significant biases, uncertainties, and imprecisions in reservoir models and furthermore are not validated by process-based modeling approaches as one should expect from any scientific protocol. This lack of validation represents a fundamental scientific gap in classical reservoir-characterization work flows that is generally avoided in other scientific domains such as physics by iterations combining experimentation and process-based models to verify deterministic interpretations and hypothesis. The paradox is that this virtuous scientific method is applied at the ultimate stage of the reservoir flow modeling with the classical “flow history matching,” implying the following strong hypothesis (Fig. 1a): If the dynamic model obtained from the upscaled static model matches the dynamic history and the flow records of the studied field and carbonate reservoir, then the geological model, including the deterministic stratigraphic and sedimentary interpretations, is validated. Reservoir flow and dynamic behavior certainly are controlled by initial geological conditions, but those are not dependent on flow processes. According to fundamental scientific principles, geological interpretations and deterministic models must be validated by geological process-based models. To fill this scientific gap in the presented carbonate-reservoir characterization approach, the authors introduce process-based stratigraphical and sedimentological models that are calibrated on pertinent, well-studied outcrop analogs.

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Marshall, Charles R. "Confidence intervals on stratigraphic ranges with nonrandom distributions of fossil horizons". Paleobiology 23, n. 2 (1997): 165–73. http://dx.doi.org/10.1017/s0094837300016766.

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A generalized method for calculating confidence intervals on the position of the true end point of a stratigraphic range when the distributions of fossil horizons is nonrandom is presented. The method requires a quantitative measure of collecting and/or preservation biases with stratigraphic position. This fossil recovery potential function may be based on (among other variables) bedding-plane surface areas, or, given a water depth curve, an a priori estimate of the preservation potential with water depth. The approach assumes that the observed distribution of fossil horizons is consistent with the distribution predicted by the fossil recovery potential function, an assumption that must be tested before the method is applied. Unlike previous methods for calculating confidence intervals on the end points of stratigraphic ranges, this method may be applied when the number of fossil horizons is correlated with stratigraphic position. The approach should only be applied to sections that have been sampled continuously, or approximately continuously. Its efficacy will depend on how accurately fossil recovery potentials can be determined. A method is also presented for estimating the probability that a species became extinct during a major hiatus in the rock record.

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Eagan, William E. "Reading the Geology of Canada: Geological Discourse as Narrative". Scientia Canadensis 16, n. 2 (8 luglio 2009): 154–64. http://dx.doi.org/10.7202/800352ar.

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ABSTRACT This article suggests that Sir William Logan's Geology of Canada can be read as a narrative describing the past dynamic changes that shaped the present structure of the earth. The author also suggests, since the foundation of nineteenth century geology was a bio-stratigraphic consensus that combined stratigraphy and the fossil record, that the use of a narrative offered Logan a dynamique method for presenting his central argument.

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Guo, Feng, Changshuan Ji, Shenghua Lai e Lei Zhang. "A method of establishing high-resolution isochronous stratigraphic framework in 3D seismic data volume". Stratigraphy 20, n. 2 (2023): 143–54. http://dx.doi.org/10.29041/strat.20.2.04.

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The establishment of a high-frequency sequence stratigraphic framework (short-term cycles) is the basis of seismic sedimentology research, which provides a new way to establish a high-resolution isochronous stratigraphic framework using 3D-seismic data. The linear interpolation between reference seismic reflections is used to establish a high-resolution isochronous stratigraphic framework (stratal slices). By carefully calibrating time-depth relationships, a corresponding relationship between short-term cycle (high-frequency cycle) interfaces and stratal slices is created. Five reference seismic reflections correspond to maximum flood surfaces. The results show that 311 isochronous stratal slices are formed in the 90 degree phase of the 3D seismic data set. Reference seismic reflection does not change with frequency. The event axis of reference for isochronous seismic reflection often corresponds to the most obvious isochronous interfaces. This method can establish a high-resolution isochronous stratigraphic framework in areas lacking drilling data in a 3D seismic data set. When geological dating data is available, the stratal slices can be further calibrated to absolute geological time, and a paleogeological map can be constructed from the seismic data set. This case study also illustrates the theoretical and practical significance of this method.

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Møyner, Olav, e Knut-Andreas Lie. "The Multiscale Finite-Volume Method on Stratigraphic Grids". SPE Journal 19, n. 05 (25 marzo 2014): 816–31. http://dx.doi.org/10.2118/163649-pa.

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Summary Finding a pressure solution for large and highly detailed reservoir models with fine-scale heterogeneities modeled on a meter scale is computationally demanding. One way of making such simulations less compute-intensive is to use multiscale methods that solve coarsened flow problems by use of a set of reusable basis functions to capture flow effects induced by local geological variations. One such method, the multiscale finite-volume (MsFV) method, is well-studied for 2D Cartesian grids but has not been implemented for stratigraphic and unstructured grids with faults in three dimensions. We present an open-source implementation of the MsFV method in three dimensions along with a coarse partitioning algorithm that can handle stratigraphic grids with faults and wells. The resulting solver is an alternative to traditional upscaling methods, but can also be used for accelerating fine-scale simulations. To achieve better precision, the implementation can use the MsFV method as a preconditioner for Arnoldi iterations using the generalized minimal residual (GMRES) method or as a preconditioner in combination with a standard inexpensive smoother. We conduct a series of numerical experiments in which approximate solutions computed by the new MsFV solver are compared with fine-scale solutions computed by a standard two-point scheme for grids with realistic permeabilities and geometries. On the one hand, the results show that the MsFV method can produce accurate approximations for geological models with pinchouts, faults, and nonneighboring connections, but on the other hand, they also show that the method can fail quite spectacularly for highly heterogeneous and anisotropic systems in a way that cannot efficiently be mitigated by iterative approaches. Thus, the MsFV method is, in our opinion, not yet sufficiently robust to be applied as a black-box solver for models with industry-standard complexity. However, extending the method to realistic grids is an important step on the way toward a fast and accurate multiscale solution of large-scale reservoir models. In particular, our open-source implementation provides an efficient framework suitable for further experimentation with partitioning algorithms and MsFV variants.

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23

Zhou, Cuiying, Jinwu Ouyang, Weihua Ming, Guohao Zhang, Zichun Du e Zhen Liu. "A Stratigraphic Prediction Method Based on Machine Learning". Applied Sciences 9, n. 17 (29 agosto 2019): 3553. http://dx.doi.org/10.3390/app9173553.

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Abstract (sommario):

Simulation of a geostratigraphic unit is of vital importance for the study of geoinformatics, as well as geoengineering planning and design. A traditional method depends on the guidance of expert experience, which is subjective and limited, thereby making the effective evaluation of a stratum simulation quite impossible. To solve this problem, this study proposes a machine learning method for a geostratigraphic series simulation. On the basis of a recurrent neural network, a sequence model of the stratum type and a sequence model of the stratum thickness is successively established. The performance of the model is improved in combination with expert-driven learning. Finally, a machine learning model is established for a geostratigraphic series simulation, and a three-dimensional (3D) geological modeling evaluation method is proposed which considers the stratum type and thickness. The results show that we can use machine learning in the simulation of a series. The series model based on machine learning can describe the real situation at wells, and it is a complimentary tool to the traditional 3D geological model. The prediction ability of the model is improved to a certain extent by including expert-driven learning. This study provides a novel approach for the simulation and prediction of a series by 3D geological modeling.

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24

Tellez, Javier, Matthew J. Pranter, Carl Sondergeld, Chandra Rai, Jing Fu, Heyleem Han, Son Dang e Chris McLain. "Mechanical stratigraphy of Mississippian strata using machine learning and seismic-based reservoir characterization and modeling, Anadarko Basin, Oklahoma". Interpretation 9, n. 2 (27 aprile 2021): SE53—SE71. http://dx.doi.org/10.1190/int-2020-0167.1.

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The Sooner Trend in the Anadarko (Basin) in Canadian and Kingfisher counties play primarily produces oil and gas from Mississippian strata. The interval consists of interbedded argillaceous mudstones and calcareous siltstones. Such a contrast in rock composition is linked directly to the mechanical stratigraphy of the strata. Brittle (calcareous siltstones) and ductile beds (argillaceous mudstones) are related to the sequence-stratigraphic framework at different scales. We have used seismic and well-log data to estimate and map the geomechanical properties’ distribution and interpret the mechanical stratigraphy of rocks within the Mississippian strata. First, we defined the parasequences that form the main reservoir zones of the Meramecian-Mississippian strata. Once we established the stratigraphic framework, we estimated and compared rock brittleness index (BI) using two independent laboratory-based measurements from the core. The first method, the mineralogical-derived BI, uses mineralogical composition inverted from Fourier-transform infrared spectroscopy analyses, whereas the second method, the mechanical-derived BI, involves measurements of compressional and shear velocities from core plugs. We use the data from core-plug velocity measurements along with well logs and an artificial neural network approach to establish relationships among the geomechanical properties, well logs, and acoustic impedance values. We then applied these relationships to generate 3D geomechanical models constrained to seismic volumes. The resulting grid distributions illustrate the stratigraphic variability of the properties at the parasequence scale. Overall, brittle strata decrease in thickness and abundance basinward as the frequency of interbedded brittle and ductile zones increases and gradually transitions into thin calcite-cemented siltstones and clay-rich mudstones. Analysis of the production performance of selected horizontal wells drilled within the Mississippian strata indicates that the proportion of brittle and ductile rocks along the well path drilled and the drilled area vertical stacking pattern play a significant role in hydrocarbon production for these Mississippian units.

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25

Li, Yong Quan, e Qing Huan Wang. "Study of Stratigraphic Classification Considering Construction of Underground Warehouse in China". Advanced Materials Research 864-867 (dicembre 2013): 1083–86. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.1083.

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In this paper, the knowledge about stratigraphic classification is introduced in detail. According to several hundred geological survey report in china, one new method about stratigraphic classification is put forward, by which rocks are divided into three categories on the base of Protodyakonov's coefficient f, and soils are divided into three categories on the base of geological age. The method about stratigraphic classification put forward is helpful for construction of underground warehouse in China.

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26

Frolov, D. M., Yu G. Seliverstov, A. V. Koshurnikov e V. E. Gagarin. "AI methods application for classifying stratigraphic layers of snow cover with Snow micro pen device". BIO Web of Conferences 84 (2024): 02009. http://dx.doi.org/10.1051/bioconf/20248402009.

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In this work, AI methods were used to classify stratigraphic layers of the snow strata using measurements from the snow micro pen device. The data from the device were processed and the classified stratigraphic layers of the snow strata were compared with the direct snow pitting data. In the future, it was possible to classify stratigraphic layers of the snow strata using the available classified data of the device by the K-nearest neighbours clustering method according to the newly obtained data of the device without additional manual pitting.

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27

Gladenkov, Yuri. "The new Russian Stratigraphic Code and some problems of stratigraphic classification". Stratigraphy 4, n. 2-3 (2007): 169–72. http://dx.doi.org/10.29041/strat.04.2.10.

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A new version of Stratigraphic Code of Russia was published in 2006. The suggested approach to the stratigraphic classification somewhat differs from that of the International Stratigraphic Guide. Stratigraphic categories consist of primary (chronostratigraphic) and auxiliary (according to method applied). Primary units may be of global (stages and others), regional (regional stages, provincial zones), and local (suites) scale. The chronozone is considered to be a part of the stage and belongs to primary units. Debatable problems, particularly different opinions on a role of lithostratigraphy and on the GSSP concept are discussed.

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28

Weninger, Bernhard. "Stratified 14C Dates and Ceramic Chronologies: Case Studies for the Early Bronze Age at Troy (Turkey) and Ezero (Bulgaria)". Radiocarbon 37, n. 2 (1995): 443–56. http://dx.doi.org/10.1017/s0033822200030927.

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Abstract (sommario):

Prehistoric tell stratigraphies, like deep-sea sediments or peat deposits, store information about past atmospheric 14C variations. By matching the 14C ages on charcoal samples from settlement deposits with the tree-ring calibration curve, estimates for the time span covered by successive stratigraphic phases can be derived. This method is applied to 14C data from the tell mounds at Troy, Turkey and Ezero, Bulgaria. I compare the derived chronologies with the results of pottery shape seriation using correspondence analysis.

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29

Zhou, Guangzhao, Zhiming Hu, Xianggang Duan e Jin Chang. "Identification of sequence stratigraphy in the Dongying Formation of the Liaoxi low uplift, Bohai Bay Basin, China". Canadian Journal of Earth Sciences 57, n. 5 (maggio 2020): 647–61. http://dx.doi.org/10.1139/cjes-2018-0276.

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A change in sea level (or lake level) causes a change in accommodation space and sediment compensation, which then controls the formation and evolution of sequences. A multidisciplinary approach based on the integration of clay minerals, major and trace elements, paleosalinity, and three-dimensional seismic data were applied to interpret the stratigraphic sequence of the Dongying Formation in the Liaoxi low uplift. The sequence surface indicates that multistage tectonic action, paleoclimate, paleosalinity, and lake level change jointly controlled the sequence stratigraphy. The illite and illite–smectite mixed layers indicate an arid to semi-arid climate, whereas kaolinite implies humid conditions. Based on this principle, it is clear that the stratigraphic sequence is closely related to paleoclimate. Interpretation of the continental or marine character of the sediments via paleosalinity is increasingly based on the concentration of some trace elements. Hence, the sequence surface can be better evaluated through paleosalinity data. Based on the Sr/Ba and boron content, paleosalinity was evaluated and the sequence boundary was identified. Analysis of the concentration of major and trace elements was used to identify the lithology of the sedimentary region and further discern the stratigraphic sequence. These sequences are composed of lowstand, transgressive, and highstand system tracts. The work herein aimed to understand the reasons for the changes in sequences under the paleoclimate. In addition, major and trace elements, studied together with paleosalinity and clay mineral content, result in the determination of implications for sequence stratigraphy in many other basins. This paper can provide a novel method for comprehensively discerning a sequence surface.

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30

Stirling, Eleanor J., Edith M. G. Fugelli e Mark Thompson. "The edges of the wedges: a systematic approach to trap definition and risking for stratigraphic, combination and sub-unconformity traps". Geological Society, London, Petroleum Geology Conference series 8, n. 1 (3 febbraio 2017): 273–86. http://dx.doi.org/10.1144/pgc8.19.

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AbstractIn recent years, stratigraphic and combination traps such as Buzzard (UK North Sea) and Jubilee (Ghana) have attracted much industry attention. Such trap types are generally considered higher risk than structural traps, and understanding them represents a challenge for explorers, as numerous less successful (often amplitude-driven) attempts have demonstrated. Owing to their perceived high risk, stratigraphic traps are often drilled late in a basin's exploration history; however, we assert that consideration of stratigraphic traps should be part of any frontier exploration programme because they occur in all basin types and depositional settings, and allow new plays to be opened up. Additionally, stratigraphic, combination and sub-unconformity traps offer the chance to rejuvenate exploration in mature basins, as recent discoveries like the Edvard Grieg Field (Norwegian North Sea) have shown.Focusing on clastic systems, and using a combination of seismic examples and models, we present two aspects of stratigraphic trap exploration: (1) the regional and local factors that favour the development of stratigraphic trap edges; and (2) a systematic method for defining and risking the trap edges, avoiding the common problem of over-risking. These two methods, used together and applied consistently, allow explorers to focus on the right area of a basin and to risk stratigraphic traps appropriately, for a fair comparison with structural traps.

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31

Huelsenbeck, John P. "Comparing the stratigraphic record to estimates of phylogeny". Paleobiology 20, n. 4 (1994): 470–83. http://dx.doi.org/10.1017/s009483730001294x.

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The age of first occurrence of taxa remains an underutilized source of information in phylogenetic analysis. In this paper I develop a method whereby one can measure the fit of the stratigraphic record to an estimated phylogenetic tree. The method works as follows: (1) each of the internal nodes excluding the root node of a phylogenetic tree is visited, (2) the oldest age of first occurrence for the taxa above the node is compared to the oldest age of first occurrence for the sister node, and (3) if the age above the node is the same age or younger than the age below the node, then the node is stratigraphically consistent. A measure of the total fit of the stratigraphic record to the tree is the proportion of nodes that are stratigraphically consistent (expressed as the stratigraphic consistency index, SCI). This measure of stratigraphic fit is sensitive to errors in phylogenetic estimation as well as to missing lineages (or parts of lineages). The significance of the fit of the stratigraphic record to the tree can be determined through a permutation approach that generates the null distribution for SCI under the hypothesis that the stratigraphic fit is no better than would be expected at random. The method is applied to several studies taken from the literature. Almost all published trees had significant SCI values, meaning the trees fit the stratigraphic record quite well. Applications of stratigraphic consistency for determining the confidence that should be placed in a phylogenetic estimate, for determining the root of a tree, and as a modified optimality criterion for estimating phylogenetic trees are discussed.

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32

Li, Xinshuai, Xuesong Yang, Huilai Wang, Chenlin Wu, Jun Xie, Qiongyao Pu, Xuecai Zhang, Xiaofan Hao e Yan Li. "Accurate identification of traps and pinch-outs on a stratigraphic reservoir-A case from Hala’alate Mountain in the Junggar Basin, China". PLOS ONE 19, n. 5 (31 maggio 2024): e0303467. http://dx.doi.org/10.1371/journal.pone.0303467.

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Abstract (sommario):

In the investigation of stratigraphic reservoirs, a significant discrepancy frequently exists between the delineation of the formation pinch-out line as traced using the characteristics of seismic wave reflections and the actual location of the formation pinch-out line. This has been the main problem restricting further hydrocarbon exploration and development. In this study, Hala’alate Mountain on the northwestern margin of the Junggar Basin is taken as an example for carrying out the study of stratigraphic reservoirs by integrating logging, drilling, and 3D seismic data. On the one hand, in studies based on the identification of formation pinch-out points using seismic data, the identification error of reservoir pinch-out lines is reduced by the improved included angle extrapolation method by utilizing the half energy attribute. On the other hand, the Poisson’s ratio curve is reconstructed using acoustic curves and oil-gas sensitive logging, then the reservoir oil-bearing facies zone is predicted using Poisson’s ratio post-stack genetic inversion to comprehensively analyze the controlling factors of stratigraphic reservoirs. The study area mainly features structural lithologic reservoirs, structural stratigraphic reservoirs and stratigraphic overlaps that pinch out reservoirs. The boundary of a stratigraphic reservoir is affected by the dip angle of the unconformity surface, the formation dip angle, and other factors. The improved included angle extrapolation method improves the identification accuracy of stratigraphic overlap pinch-out reservoirs. The reservoir distribution then is calculated according to Poisson’s ratio inversion, improving the prediction accuracy for the reservoir. This method improves the predictive effect for stratigraphic reservoirs and provides a new idea for the exploration and development of similar reservoirs.

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33

Wagner, Peter J. "Stratigraphic tests of cladistic hypotheses". Paleobiology 21, n. 2 (1995): 153–78. http://dx.doi.org/10.1017/s009483730001318x.

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Cladograms predict the order in which fossil taxa appeared and, thus, make predictions about general patterns in the stratigraphic record. Inconsistencies between cladistic predictions and the observed stratigraphic record reflect either inadequate sampling of a clade's species, incomplete estimates of stratigraphic ranges, or homoplasy producing an incorrect phylogenetic hypothesis. A method presented in this paper attempts to separate the effects of homoplasy from the effects of inadequate sampling. Sampling densities of individual species are used to calculate confidence intervals on their stratigraphic ranges. The method uses these confidence intervals to test the order of branching predicted by a cladogram. The Lophospiridae (“Archaeogastropoda”) of the Ordovician provide a useful test group because the clade has a good fossil record and it produced species over a long time. Confidence intervals reject several cladistic hypotheses that postulate improbable “ghost lineages.” Other hypotheses are acceptable only with explicit ancestor-descendant relationships. The accepted cladogram is the shortest one that stratigraphic data cannot reject. The results caution against evaluating phylogenetic hypotheses of fossil taxa without considering both stratigraphic data and the possible presence of ancestral species, as both factors can affect interpretations of a clade's evolutionary dynamics and its patterns of morphologic evolution.

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Sastrawan, Febrian Dedi, Meidi Arisalwadi e Rahmania. "Analyzing of 1D Resistivity Data to Determine Subsurface Condition on the Development Area of Institut Teknologi Kalimantan (ITK) Balikpapan". Advances in Science and Technology 104 (febbraio 2021): 41–45. http://dx.doi.org/10.4028/www.scientific.net/ast.104.41.

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Abstract (sommario):

Information of subsurface stratigraphy is needed during the process of preparing multi-story buildings to avoid problems in determining the level of multi-story building piles. This research was conducted using the geoelectric method to study the subsurface stratigraphic conditions in the area. Based on the measurement results, we find an overview of the subsurface stratigraphic conditions consisting of soil in the first layer with resistivity values ranging from 305 to 570 Ωm, the soil in the study area is red-yellow, namely podsolic soil mixed with sand and gravel. The second layer is clay layer by water saturated with resistivity values between 15 to 44 Ωm, and the third layer with resistivity values varying from 112 to 341 detected from the surface is sandy clay. Insertion of coal at the first measurement point was detected buried at a depth of 17 m from the surface with a resistivity value of 962 Ωm.

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35

Qin, Lei, Cun Lei Li, Yan Li e Jing Zhe Li. "High Resolution Sequence Stratigraphic Study of Single Sand Body in the Complex Reservoir in High Water-Cut Period: Take the Member I of Qing Shankou Formation of Hei 96 Block of Songliao Basin for Example". Applied Mechanics and Materials 339 (luglio 2013): 732–36. http://dx.doi.org/10.4028/www.scientific.net/amm.339.732.

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Abstract (sommario):

With the method of the high resolution sequence stratigraphy and sedimentology theory, oil-bearing sand bodies have been accurately recognized and descripted which could provide precisely geological data for 3-D modeling and numerical simulation. It has the vital significance for the development of oilfield during the late stage of high water cut. According to the drilling, logging, seismic and analytical experiments data, the results show that the study area can be divided into one long-term base level cycle, four middle-term base level cycles, sixteen short-term base level cycles and twenty-eight super short-term base level cycles. Based on the classification of base-level cycles, control functions of cycles which have effects on the sediment environment have been discussed. And with the application of the chronostratigraphic correlation fine stratigraphic correlation, 10 high resolution sequence stratigraphic frameworks are established in the direction that is parallel and perpendicular to the source.

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Li, Ang, Lai Xing Cai, Shuang Liu e Qi Li. "Characteristics of Sedimentation Evolution Based on the Sequence Stratigraphic Frameworks in Shahezi Formation of Southern Xujiweizi Fault Depression". Advanced Materials Research 1010-1012 (agosto 2014): 1359–64. http://dx.doi.org/10.4028/www.scientific.net/amr.1010-1012.1359.

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Abstract (sommario):

Many scholars in China introduced the theory of sequence stratigraphy,applying to Chinese continental fault depression lake, they have made a lot of achievements in scientific research. However, there are still a lot of controversy according to the establishment in Shahezi group of sequence stratigraphic framework in Xujiaweizi fault depression.Sequence boundary identification method in this paper is based on the “instruction of Vail’s sequence stratigraphy theory, identification of seismic unconformity, verification by using logging methords”. And, following the principle of isochronous ,sequence stratigraphic framework of this region is established clearly. The southern Xujiaweizi fault depression in Shahezi group is divided into 1 second grade sequence, in the interior distributed SQ1-SQ4 4 third grade sequences from the bottom. Developmental stages at the bottom of SQ1 and the top of SQ4, basin is small and water is shallow. However, Developmental stages in SQ2 and SQ3,water enters the lake basin continuously, formed a sedimentary background of “wide basin and deep water”. In addition, each of the three grade sequence has split structure, the lake transgressive domain and lake regression domain two system tracts. Besides, the reversed order para-sequence sets caused by the lake regression and progradation set on the positive para-sequence sets caused by the lake transgression and retrogradation. On the basis of sequence stratigraphic division and correlation, conbined with the regional construction and the supply of provenance ,the sedimentary sequence framework of evolution characteristics are studied.That fan delta,braided river delta, lacustrine are the main facies types in study area. Characteristics of sedimentary evolution there are like this: the characteristics of sedimentation evolution show framework controls sand, succession of evolution, separated-source sedimentary, contiguously distribution.

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Mudge, W. J., e A. B. Thomson. "THREE-DIMENSIONAL GEOLOGICAL MODELLING IN THE KINGFISH AND WEST KINGFISH OIL FIELDS: THE METHOD AND APPLICATIONS". APPEA Journal 30, n. 1 (1990): 342. http://dx.doi.org/10.1071/aj89022.

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RESMAP is an Exxon proprietary program that makes possible the building of three-dimensional geological models. The models consist of millions of tabular cells contained within a stratigraphic framework. The models are generated by the integration of log analysis, seismic interpretation and the geologist's well picks and interpretation.RESMAP models are easy to access for generating structural and stratigraphic geological cross-sections. Maps such as structure, top of porosity and net sand percentage can be generated as well as subcrop and supercrop maps. Hydrocarbon-in-place estimates are also made from the model.The Kingfish and West Kingfish fields each possess a complex stratigraphic framework and exhibit rapid facies changes in the nearshore marine sediments. Techniques available in RESMAP enable the integration of the well data and seismic maps to produce an accurate stratigraphic framework containing the geometries of truncation onlap and downlap. The interpolation of porosity data from the wells successfully captures the facies distribution. This is due to the excellent well spacing in the vicinity of the facies changes and the ability to place geological constraints on the interpolation.The model provides a valuable communication tool for the mass of data present in a field. The model can also be updated quickly upon receipt of new data, providing a dynamic reservoir description on which to base future field management.

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Burgess, Peter M. "Identifying ideal stratigraphic cycles using a quantitative optimization method". Geology 44, n. 6 (28 aprile 2016): 443–46. http://dx.doi.org/10.1130/g37827.1.

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39

Brown, Iain M. "A new method for correlation of multiple stratigraphic sequences". Computers & Geosciences 23, n. 6 (luglio 1997): 697–700. http://dx.doi.org/10.1016/s0098-3004(97)00046-0.

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40

Villalobos, Roberto. "new proposal for the Architectural Stratigraphic Analysis and the resulting diagram". Acta IMEKO 13, n. 2 (16 maggio 2024): 1–8. http://dx.doi.org/10.21014/actaimeko.v13i2.1729.

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Abstract (sommario):

The stratigraphic analysis is a non-destructive method based on archaeology that illustrates the relationships and sequences of the stratigraphic layers of excavations by listing all their constituting elements, to be later represented in a stratigraphic diagram. Although the constant improvements and applications of the stratigraphic analysis in several scientific fields since 1973, this study proposes specific modifications to the current method as well as an adaptation of the diagram scheme to each case study of conservation. The main goal of this study was the elaboration of a detailed and comprehensive diagram that encompasses the entire monument, rather than one for each individual section of the monument. The first step was the identification of the main stratigraphic units and their classification based on their primary function: structural or decorative. The second step concerned a simplification of the current relationships of the architectural units into three groups, according to their roles within the entire system to obtain a simpler stratigraphic sequence. The final step was the new incorporation of pathology-related information and the addition of the missing elements as a reconstruction process. These adjustments allowed the diagram to arrange all data gathered from heritage analysis and will permit historians, architects, archaeologists, and others to engage in a global reading of the built. The stratigraphic diagram will serve as a tool to visually represent the analysis and synthesis in a coded manner, which will be comprehensible to both the researchers and the scientific community.

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41

Wagner, Peter J. "A likelihood approach for evaluating estimates of phylogenetic relationships among fossil taxa". Paleobiology 24, n. 4 (1998): 430–49. http://dx.doi.org/10.1017/s0094837300020091.

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Abstract (sommario):

Estimates of phylogenetic relationships among fossil taxa implicitly provide hypotheses about the quality of the fossil record. Phylogenetic inferences also provide hypotheses about character evolution. The likelihood of any hypothesis that makes predictions about two data sets is simply the likelihood of the hypothesis given the first data set times the likelihood of the same hypothesis given the second data set. In this case, data set 1 represents stratigraphy and data set 2 represents morphology. Statistical methods exist for determining the likelihood of hypothesized levels of sampling. The likelihood of a hypothesized amount of character change yielding a particular most-parsimonious solution (i.e, L[hypothesized length | parsimony length] can be evaluated with simulations. A reanalysis of hyaenid phylogeny based on published character and stratigraphic data is presented here, using the maximum likelihood method. Two trees are found, depending on assumptions about ambiguous species, which are 11 and 10 steps longer than the most parsimonious tree (61 or 60 vs. 50 steps). However, the trees invoke far less stratigraphic debt (9 or 12 units vs. 47 units as measured in Mammal Zones). An important feature of the results is that the most likely tree length given hyaenid character data is estimated to be 56 to 62 steps (depending on the model of character evolution) rather than 50 steps. The likelihood tree suggests stronger trends toward bone-crushing specializations than does the parsimony tree and further suggests that high levels of homoplasy caused parsimony to underestimate the true extent of those trends. Simulations based on the character data and fossil record of hyaenids suggest that the maximum likelihood method is better able to estimate correct trees than is parsimony and somewhat better able to do so than previously proposed phylogenetic methods incorporating stratigraphy.

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42

Alroy, John. "Appearance event ordination: a new biochronologic method". Paleobiology 20, n. 2 (1994): 191–207. http://dx.doi.org/10.1017/s0094837300012677.

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Abstract (sommario):

The fundamental goal of biochronology is ordering taxonomic first and last appearance events. The most useful biochronologic data are of the form “the first appearance event of one taxon predates the last appearance event of a second taxon” (FAE < LAE). FAE < LAE data sets are unusually reliable because they converge on a unique solution with greater sampling. The fact that the FAE of one taxoni< the LAE of another taxonjalways can be inferred either ifiis found lower thanjin a stratigraphic section, or ifiandjco-occur in at least one taxonomic list. Thus, FAE < LAE data accurately synthesize two disparate sources of information: routine biostratigraphic observations and taxonomic lists that may have no stratigraphic context. Appearance event ordination, the new method introduced here, is intended to summarize FAE < LAE data. The algorithm is founded on the following parsimony criterion: arrangements of FAEs and LAEs should always imply FAEi< LAEjwhen this is known, and otherwise imply LAEj< FAEiwhenever possible. The technique differs from others related to correspondence analysis in its use of FAE < LAE data and explicit definition as a parsimony method. The algorithm is even more unique in that it uses different subsets of FAEi< LAEjstatements at each iterative step, converging on separate sets of scores for the FAEs and LAEs. After arranging either the FAEs or the LAEs on the basis of their scores, the other set of scores can be discarded and the best arrangement of the remaining events can be inferred directly. An analysis of the Plio-Pleistocene mammalian record in the Lake Turkana region is used to illustrate the method. Biochronologic resolution on the order of 0.2-1.5 m.y. is achieved. The Turkana species lists by themselves demonstrate enough FAEi< LAEjrelationships to resolve the basic biochronologic pattern, but stratigraphic information is still of great use.

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Shen, Yan-Gen, An-Bo Li, Jian-Chu Huang, Guo-Nian Lü e Kai-Li Li. "Three-dimensional modeling of loose layers based on stratum development law". Open Geosciences 14, n. 1 (1 gennaio 2022): 1480–500. http://dx.doi.org/10.1515/geo-2022-0440.

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Abstract (sommario):

Abstract Loose layers are the locus of human activities. The high-quality 3D modeling of loose layers has essential research significance and applicability in engineering geology, hydraulic and hydroelectric engineering, and urban underground space design. To address the shortcomings of traditional 3D loose-layer modeling based on borehole data, such as the lack of bedrock surface constraints, simple strata pinch-out processing, and the higher fitting error of the strata surface, a 3D loose-layer modeling method based on the stratum development law is proposed. The method mainly uses three different virtual boreholes, bedrock-boundary virtual boreholes, pinch-out virtual boreholes, and densified virtual boreholes, to control the stratigraphic distribution. Case studies demonstrate the effectiveness of this 3D loose-layer modeling method in the Qinhuai District of Nanjing and Hangkonggang District of Zhengzhou. Compared to the previous methods that interpolated stratigraphic surfaces with elevation information, the method proposed in this article interpolates the stratum thickness based on stacking, which could improve the interpolation accuracy. In the area where the loose layers and exposed bedrock are alternately distributed, stratigraphic thickness errors’ mean and standard deviation decreased by 2.11 and 2.13 m. In the pure loose-layer area, they dropped by 0.96 and 0.33 m. In addition, the proposed approach allows us to infer the different stratigraphic distribution patterns accurately and complete 3D loose-layer model construction with higher accuracy and a good visualization effect.

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44

Huelsenbeck, John P., e Bruce Rannala. "Maximum likelihood estimation of phylogeny using stratigraphic data". Paleobiology 23, n. 2 (1997): 174–80. http://dx.doi.org/10.1017/s0094837300016778.

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The stratigraphic distribution of fossil species contains potential information about phylogeny because some phylogenetic trees are more consistent with the distribution of fossils in the rock record than others. A maximum likelihood estimator of phylogeny is derived using an explicit mathematical model of fossil preservation. The method assumes that fossil preservations within lineages follow an independent Poisson process, but can be extended to include other preservation models. The performance of the method was examined using Monte Carlo simulation. The performance of the maximum likelihood estimator of topology increases with an increase in the preservation rate. The method is biased, like other methods of phylogeny estimation, when the rate of fossil preservation is low; estimated trees tend to be more asymmetrical than the true tree. The method appears to perform well as a tree rooting criterion even when preservation rates are low. We suggest several possible extensions of the method to address other questions about the nature of fossil preservation and the process of speciation and extinction over time and space.

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45

Fuller, J. "Stratigraphic Stand-Off at the 49th Parallel". Earth Sciences History 24, n. 2 (1 gennaio 2005): 247–64. http://dx.doi.org/10.17704/eshi.24.2.w220364922xw6906.

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The 49th Parallel divides the western Prairies between Canada and the United States, crossing the central part of the Williston basin and marking the International boundary that separates Saskatchewan from the States of Montana and North Dakota. Discoveries of oil in this area during the 1950s triggered widespread geological activity, and revealed significant differences of stratigraphical understanding on each side of the border. Problems seemed to arise from contrasts between ‘American' and ‘English' interpretations of stratigraphical method, particularly for the oil-producing zones of the Mississippian. This study analyzes the differing points of view, and presents historical reasons for them. Difficulties with stratigraphical method and nomenclature in the 1950s were quite real, becoming the subject in 1959 of a special AAPG-SEPM conference at Dallas. Had the delegates attending that meeting (including the present author) possessed a little more history, they would have known that an ‘American' or mineral-focused view of stratigraphy had originated in a German hard-rock mining terrane, principally through the teaching of Abraham Werner. From there, during the first years of the 19th century, it traveled via Scotland to the State of New York, where, from Amos Eaton's Rensselaer School at Troy, it spread to most of the newly-formed State geological surveys. Some years later, on the other hand, an ‘English' or ‘stratum-focused' view of stratified formations migrated across the Atlantic from the pastoral landscapes and gently inclined rock-formations of southern England, where mapping had tended to discount their mineral content in favor of their observable order and continuity.

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46

Marshall, Charles R. "Confidence intervals on stratigraphic ranges: partial relaxation of the assumption of randomly distributed fossil horizons". Paleobiology 20, n. 4 (1994): 459–69. http://dx.doi.org/10.1017/s0094837300012938.

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The equations for calculating classical confidence intervals on the end points of stratigraphic ranges are based on the restrictive assumption of randomly distributed fossil finds. Herein, a method is presented for calculating confidence intervals on the end-points of stratigraphic ranges that partially relaxes this assumption: the method will work for any continuous distribution of gap sizes, not just those generated by random processes. The price paid for the generality of the new approach is twofold: (1) there are uncertainties associated with the sizes of the confidence intervals, and (2) for large confidence values (e.g., 95%) a rich fossil record is required to place upper bounds on the corresponding confidence intervals. This new method is not universal; like the method for calculating classical confidence intervals it is based on the assumption that there is no correlation between gap size and stratigraphic position. The fossil record of the Neogene Caribbean bryozoan Metrarabdotos is analyzed with the new approach. The equations developed here, like those for classical confidence intervals, should not be applied to stratigraphic ranges based on discrete sampling regimes, such as those typically established from deep-sea drilling cores, though there are exceptions to this rule.

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Zhu, Jixiang, Xiaoyuan Zhou, Guanghui Zhang e Qian Wang. "Quaternary Depositional Framework of the Xiong’an New Area: A 3D Geological Modeling Approach Based on Vector and Grid Integration". Sustainability 14, n. 6 (14 marzo 2022): 3409. http://dx.doi.org/10.3390/su14063409.

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The Quaternary stratigraphic unit is an important underground space resource for sustainable urban development. It is of great significance to understand the spatial variation characteristics of the Quaternary stratigraphic structure and its internal attributes. However, due to the openness and complexity of the Quaternary sedimentary environment, the sedimentary characteristics of Quaternary stratigraphic units are often very complex and difficult to accurately analyze. In this study, a method for analyzing Quaternary sedimentary characteristics via 3D geological modeling based on vector and grid integration is proposed. Based on this method, the Quaternary depositional framework of Xiong’an New Area is established. The results show that the study area is mainly composed of seven Quaternary strata with different sedimentary origins, and the 3D spatial variation characteristics of lithology in each stratum are unique. Taking the vector framework model as the constraint boundary, this study constructs the lithology stochastic model of each Quaternary stratigraphic unit respectively, and accurately simulates the 3D spatial variation characteristics of the inner lithology of Quaternary stratigraphic units in the study area, which is of great significance for the urban planning, construction, and environmental protection of Xiong’an New Area.

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Liu, Zhen, Jin Luo, Xiangdong Wang, Weihua Ming e Cuiying Zhou. "Unique Path Method of the Pinch-Out Profile Based on Unified Stratigraphic Sequence". Geosciences 11, n. 6 (10 giugno 2021): 251. http://dx.doi.org/10.3390/geosciences11060251.

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Pinch-outs refers to the gradual thinning of the thickness of the sedimentary layer laterally until there is no deposition and are a major topic of modern research on the automated drawing of geological profiles. The rapid development of smart geological systems imposed an urgent need for high-speed, accurate methods to plot pinch-outs. However, because of their complexity, excessive number of branch paths, low rendering speed, and poor reliability in the case of large-scale data, the existing pinch-out drawing methods are inadequate and cannot satisfy the modeling needs of large-scale geological projects. To resolve these problems, based on unified stratigraphic sequences, this paper proposes a unique path method for drawing pinch-out profiles by converting the principle of plotting of pinch-outs into controlling the appearance of stratigraphic boundaries, and a high-speed and reliable method for drawing pinch-out in digital profiles is also proposed. The proposed method is successfully applied to drawing geological profiles for an urban geological project in East China, and greatly reduces the complexity of the method without reducing the drawing accuracy. Compared with those of other methods, the speed and reliability are significantly improved. Therefore, the unique path method for drawing pinch-out profiles based on a unified stratigraphic sequence proposed in the writers’ previous paper effectively avoids the excessive branch paths, slow speed, and insufficient reliability of the existing methods and provides effective and reliable support for the rapid drawing of profiles in smart geological systems.

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He, Ping, Shangfeng Zhang, Enze Xu e Chunxia Zhu. "Milankovitch cycles and the astronomical time scale of the Zhujiang Formation in the Baiyun Sag, Pearl River Mouth Basin, China". Open Geosciences 14, n. 1 (1 gennaio 2022): 1380–92. http://dx.doi.org/10.1515/geo-2022-0434.

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Abstract The Zhujiang Formation in the Baiyun Sag, Pearl River Mouth Basin, China, is formed primarily in a deep-water continental slope environment. Its chronostratigraphic framework is based on biostratigraphy and sequence stratigraphy, and its geological dating is based on micropaleontological data. This makes it difficult to obtain precise absolute ages for various geological events. In this study, gamma ray (GR) well log data from Wells Y1, Y2, and Y3 were used as paleoclimate proxies, and spectral and wavelet analyses were used to conduct cyclostratigraphic research. The results show that the Milankovitch cycles were preserved in the Zhujiang Formation in the Baiyun Sag. Stratigraphic cycles controlled by 405 and 95 ka orbital eccentricity, 40.4 ka orbital obliquity, and 23.5 ka orbital precession cycles can be identified; the signal of stratigraphic cycles controlled by the 405 ka long eccentricity cycle is the strongest. The floating astronomical time scale is constructed based on 405 ka orbital eccentricity cycle tuning of the GR series. The precise durations of the Zhujiang Formation in Wells Y1, Y2, and Y3 are 7.13, 6.93, and 7.18 Ma, and the average deposition rates are 4.68, 5.91, and 5.33 cm/ka, respectively. The Zhujiang Formation was divided into 17 fourth-, 76 fifth-, and 174 sixth-order cycles using the 405, 95, and 40.4 ka orbital periods as the dividing scales, respectively. This study provides a quantitative method for high-precision isochronous stratigraphic division and correlation in deep-water sedimentary systems.

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Marshall, Charles R. "Confidence intervals on stratigraphic ranges". Paleobiology 16, n. 1 (1990): 1–10. http://dx.doi.org/10.1017/s0094837300009672.

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Observed stratigraphic ranges almost always underestimate true longevities. Strauss and Sadler (1987, 1989) provide a method for calculating confidence intervals on the endpoints of local stratigraphic ranges. Their method can also be applied to composite sections; confidence intervals may be placed on times of origin and extinction for entire species or lineages. Confidence interval sizes depend only on the length of the stratigraphic range and the number of fossil horizons. The technique's most important assumptions are that fossil horizons are distributed randomly and that collecting intensity has been uniform over the stratigraphic range. These assumptions are more difficult to test and less likely to be fulfilled for composite sections than for local sections.Confidence intervals give useful baseline estimates of the incompleteness of the fossil record, even if the underlying assumptions cannot be tested. Confidence intervals, which can be very large, should be calculated when the fossil record is used to assess absolute rates of molecular or morphological evolution, especially for poorly preserved groups. Confidence intervals have other functions: to determine how rich the fossil record has to be before radiometric dating errors become the dominant source of error in estimated times of origin or extinction; to predict future fossil finds; to predict which species with fossil records should be extant; and to assess phylogenetic hypotheses and taxonomic assignments.

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